Friday, May 06, 2005

Water management district to be ready for 2005 hurricane season

From: Osceola News-Gazette

Regional water management officials have already begun gearing up for hurricane season, putting lessons learned into practice.

The South Florida Water Management District March 15 began its annual drawdown of the 17 lakes in the Kissimmee Basin to summer pool in anticipation of the Atlantic hurricane season, which begins June 1 and runs through Nov. 30.

Given the heavy rains in the region associated with three hurricanes and with higher than normal rainfall in general, the drawdown of Lake Tohopekaliga last year to remove muck proved a godsend, since the additional storage capacity in the lakes system beyond the normal summer levels helped prevent significant flooding.

“It certainly was fortuitous,” said Bill Graf, spokesman for the district. “Lake Tohopekaliga was four and a half feet lower in August than it otherwise would have been. Had that not happened, flooding would have been more dramatic and widespread.”

Graf said that in order to lower Lake Tohopekaliga, other lakes in the system had to be lowered as well, some by three or more feet, creating significant additional storage capacity.

“During Hurricane Frances, city of Kissimmee officials were worried because the lake level was coming up into the waterfront park and then there was a two and a half to three-foot storm surge. With the combination, there would have been, at the least, water around the train station and Kissimmee Civic Center.”

When asked what the water district had learned from the 2004 hurricane season, Graf said it already is working with city of St. Cloud officials to enlarge certain drainage structures and that bringing in the Federal Emergency Management Agency as a partner for that work would result in a greater number of federal dollars for the project and fewer local ones

The district also is developing better modeling and automated monitoring systems for Boggy, Reedy and Shingle creeks, all waterways with no flood control structures and yet with significant residential and commercial development along them.

“We didn’t have a good handle on how they would behave and where the water levels would go,” said Graf.

People who had developed knowledge of the waterways over time and who monitored the creeks provided “extremely valuable” insights in predicting flows.

He said the district also is working on improved modeling on predicting when the lakes would crest. He said that while public officials generally agree that it is better to provide a “worst case” prediction, more specific forecasts would help those same officials make better decisions about what areas, for example, should be evacuated.

At the height of the flood threat, the district moved the maximum amount of water possible through its drainage system, resulting in some damage to structures.

Structure S-65, a lock and spillway that separates Lake Kissimmee from the Kissimmee River, saw damage but the real worry was structure S- 65A, just downstream.

“Huge amounts of riprap (chunks of stone) had to be brought in because of erosion,” said Graf. “We were worried we might lose that structure.”

According to Graf, all repairs to the system have been made. The issue, he said, was that the water released through the locks, in an effort to keep communities from flooding, exceeded design.

Efforts to have additional storage available in the system are continuing as local governments negotiate with landowners for water flowage easements, a kind of “water ranching.”

Graf explained that the water district or counties, for example, negotiate agreements whereby water in times of emergency could be pumped to low-lying areas on private property for a certain monetary compensation.

“During the Lake Toho drawdown in advance of removing muck, these kind of agreements were worked out in a quick manner,” he said.

Removing the muck from East Lake Tohopekaliga is tentatively set for 2008.

New residents often misunderstand the annual lowering of the lakes, Graf said, emphasizing that a drawdown is a more drastic lowering of a lake level.

“From time to time, we’ll have a brand new resident who will have a dock built based on the winter elevation of a lake and then come summer, their dock is dry,” said Graf. “Anytime someone is planning dock construction, we’re happy to pass lake level information along to them because we don’t want people operating under the wrong assumptions. A little bit of knowledge goes a long way.”

Questions about specific lake elevations and fluctuation schedules can be directed to Bill Graf of the South Florida Water Management District’s Orlando Service Center. He can be reached at 407-858-6100, Ext. 3837, or on his cell phone at 407-908-4764. His e-mail address is wgraf@sfwmd.gov.

SFWMD’s boundaries extend from Central Florida to Lake Okeechobee, and from coast to coast, from Fort Myers to Fort Pierce, south through the Everglades to the Florida Keys and Florida Bay.

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